Field of the Invention
The present invention relates to a residual current protection device for connection to a circuit breaker or a load break switch and includes a detection device for detecting a residual current and a tripping device which is actuable by the detection device so that the circuit breaker trips as a result of actuation by the tripping device. Moreover, the present invention relates to an electrical protection configuration. The residual current protection device can be independent of the mains voltage (i.e. without any auxiliary voltage source), but also dependent on the mains voltage (i.e. with an auxiliary voltage source).
Residual current protection devices provide fault protection in low-voltage grids for the case in which a basic insulation has failed or direct touching contact is made with live parts. As a result, damage to humans, objects and livestock is prevented or reduced.
Residual current protection devices, i.e. differential current units or residual current units or functions, can be attached to conventional circuit breakers or implemented as an external, modular configuration. Alternatively, the residual current protection devices can also be integrated in compact circuit breakers. If, during operation of an installation, a residual current then occurs, the residual current is detected by the residual current protection device, and the residual current protection device trips the relevant (compact) circuit breaker and therefore disconnects the installation from the power supply.
In the case of special types of residual current protection devices, so-called auxiliary releases are provided as tripping devices. Those auxiliary releases are electromechanical systems in particular based on magnets, with which systems a movement, in particular for a latching mechanism, can be generated from an actuation signal as a result of a residual current. In a specific case, an auxiliary release can also be referred to as a tripping magnet. Depending on the function, there is a distinction between voltage releases and under voltage releases in the case of auxiliary releases. Voltage releases trip (i.e. generate a mechanical movement) when a voltage threshold is exceeded. Undervoltage releases trip when a voltage threshold is undershot.
The residual current protection device and the circuit breaker are generally disposed in separate housings. The circuit breaker can have a housing, in which one or more accessory pockets are provided. The abovementioned auxiliary release, an auxiliary switch, an alarm switch or the like can be plugged into such an accessory pocket. With those modular accessories, an electrical protection configuration, which can include a circuit breaker and a residual current protection device, is therefore capable of individualization.
There is the need to check the function of residual current protection devices at certain times or at certain time intervals. In particular, the tripping device also needs to be checked possibly in interaction with the circuit breaker with respect to functionality.